基于尺度效应曲线及信息熵的延河流域适宜DEM分辨率判定OA北大核心CSTPCD

[Objective]The aims of this study are to determine the appropriate DEM resolution for geomorphic hydrology research in a small watershed of the Loess Plateau,explore the applicability of scale effect curve and information entropy method,and provide a new perspective and approach for determining the appropriate resolution.[Methods]Taking Yanhe River Basin in the loess hilly region as the research area,ArcGIS was used to resample the original resolution DEM,obtain multiple groups of DEM with different resolutions,extract the terrain attribute values at corresponding scales,and draw two different scale effect curves('average slope-resolution'and'local variance mean-resolution'curves).Information entropy and mutual information entropy are introduced to distinguish suitable DEM resolution based on actual terrain.[Results](1)In the Yanhe River Basin with complex terrain,the results obtained by different determination methods are different,while the results of local variance mean,information entropy and mutual information entropy are similar.(2)The results of determining the appropriate resolution by different terrain attributes are different.The appropriate resolution obtained by profile curvature and plane curvature is similar(the local mean variance is 15～20 m,and the information entropy and mutual information entropy are both 15 m),and the difference of the appropriate resolution obtained by slope is greater than that obtained by curvature(the local mean variance is 20～35 m).The results of information entropy and mutual information entropy are both 20 m.[Conclusion]Both local variance mean and information entropy method are suitable for DEM resolution determination in this area,and the appropriate DEM resolution in Yanhe River Basin is 15～20 m.